The famous Fox host sharpened the differences between older, center-right Republicans and today’s young, cosmopolitan right-wingers.

I appeared on The O’Reilly Factor, Fox News’s flagship evening program, hosted by the now-ousted Bill O’Reilly, in the summer of 2015. An average number of people tuned in that night — somewhere in the neighborhood of 2 million. My conservative friends, twentysomethings, many of them from reliably red states, were not tuned in. But their parents were.

That’s telling. The O’Reilly Factor, which will air its final episode on Friday, was a massively popular news show — for a decade and a half the most popular show — on America’s most-watched cable news network. But The O’Reilly Factor was not for everyone; more to the point, it was not intended to be. Bill O’Reilly’s loyal viewers were largely older, suburban or rural, middle or lower-middle class, generally white, and Republican. At the end of 2016, O’Reilly averaged 3.3 million nightly viewers, but while viewers in the key 25-to-54 demographic increased significantly from 2015 (probably an effect of the unusual election year), they still accounted for less than one-fifth of his nightly audience.

That should not come as a surprise. O’Reilly was tailor-made for a certain viewer. An Irish Catholic from working-class Long Island, born in 1949, O’Reilly was reared by a generation with warm feelings toward FDR’s New Deal economics, came of age in the 1960s and 1970s counterculture, and launched his career amid the Reagan Revolution. These were formative experiences shared by millions of Americans. Repulsed by the radicalism of Berkeley and the Black Panthers, offended by the lecturing of Jimmy Carter (crystallized in his “malaise” speech), but not far removed from the horrors of the Great Depression and World War II, they found themselves looking back affectionately to the economic ascendancy and cultural consolidation of the 1950s. And so they landed firmly on the right side of the political spectrum — but nearer its center than we often recall today. It was this audience that Fox News targeted when it was created in 1996 and that found a representative voice on The O’Reilly Report, which launched that same year.

Bill O’Reilly carried this audience with him for two decades — an extraordinary accomplishment — and Fox News built itself up around him in the process, aiming to make further inroads into the same large audience: white, middle-class Republicans whose ideal America was receding farther into the past as the country became increasingly polarized — by culture wars, by Newt Gingrich’s guerrilla House speakership, by Bill Clinton’s adultery, and, of course, by biased media. Fox gave airtime to “movement,” Buckley-style conservatives, but its appeal was less educational than aesthetic: people like you, talking about issues you care about, using their good old American common sense. That approach characterized much of Fox’s most popular programming: Hannity & Colmes, Hannity, On the Record with Greta Van Susteren, Fox & Friends. And it tended to reinforce the broad center-right sentiments that in turn bolstered O’Reilly’s appeal. Occasionally, Fox has been more overt in its aww-shucks branding — for instance, in Heartland with John Kasich.

Of course, during this time, a different generation of conservatives grew up. Born in the late 1960s and 1970s, they came of age during the Reagan-Bush years. Often, they grew up reading National Review and Human Events, or attending lectures and conferences on Hayekian economics sponsored by Young America’s Foundation and the Intercollegiate Studies Institute. They launched their careers in a post–Cold War America. They rejected as illiberal the policies of the New Deal and the Great Society, and they sided with Samuel Huntington’s Clash of Civilizations over Francis Fukuyama’s End of History. They watched Fox News, but because it was the only option, not because it precisely spoke for them (although it did in certain general respects). A number of these conservatives are first- or second-term Republican senators.

This rough-and-ready genealogy might even include a third generation, emerging now — one whose world was shaped by September 11, Iraq, economic recession, and the hyper-partisanship of the Obama years. These conservatives are not Bill O’Reilly; they’re Ben Shapiro, Mollie Hemingway, and Mary Katharine Ham. Their media are podcasts and Twitter, and while they’re certainly combative, they are more interested in a savvy, cosmopolitan conservatism that goes toe-to-toe with progressivism on its own turf (consider Shapiro’s popular campus-speaking events) than in the countrified, bigger-government, populism-tinged conservatism embodied by Mike Huckabee.

This is only a sketch, but it helps illustrate an obvious phenomenon in right-wing politics at present: It is run through by a bold dividing line, which broadly separates first-generation right-wingers from both their children and grandchildren.

Fox News’s success has to no small degree depended on its appeal to a particular form of right-wing sentiment, and that success has sharpened a divide between groups of right-wingers with very different visions of what a ‘conservative’ America ought to look like.

The last year has revealed just how significant that divide really is. Eager for a young, conservative, idea-oriented presidential candidate, many second- and third-generation conservatives lined up behind Ted Cruz or Marco Rubio. But Donald Trump leapt into the race and unwittingly found himself the beneficiary of a center-right energy that many thought had dissipated forever. The clearest example was among the “religious Right,” where older, Moral Majority–era types (such as Jerry Falwell Jr. and Pat Buchanan) backed Trump vigorously, while younger Evangelicals (such as Southern Baptist minister Russell Moore) rejected him. A similar dynamic played out in conservative media, where Trump alienated many young, prominent conservatives (early opponents of Trump included Ben Shapiro, Katie Pavlich, and Ben Domenech) but found fierce defenders in O’Reilly and Hannity. When much of Fox News de facto backed Trump, midway through the primary season, it could hardly come as a shock: It was already obvious that the same type of person Fox had targeted for 20 years was likely to be an ardent Trump supporter.

It is difficult, of course, to distinguish cause and effect in all of this. Has the Right made Fox? Or has Fox made the Right? The answer is surely: both, to a degree. But what becomes increasingly clear is that, to the extent that Fox has made the Right, it has made a certain kind of Right and become the model for other conservative media. Tomi Lahren, a former host on Glenn Beck’s The Blaze, was attempting to re-create the glib, pugnacious Fox News model for a younger audience.

It is not clear, though, that the model can be translated — or ought to be. Fox News’s success has to no small degree depended on its appeal to a particular form of right-wing sentiment, and that success has sharpened a divide between groups of right-wingers with very different visions of what a “conservative” America ought to look like.

There are a million reasons for the inner conflicts within right-wing politics in the United States today. But this significant generational tension might justly be called, with only a hint of exaggeration, the O’Reilly factor.

— Ian Tuttle is the Thomas L. Rhodes Fellow at the National Review Institute.